1. Field
The disclosure relates to media devices, and, in particular, techniques for removing crosstalk between channels caused by ground resistance in a media device.
2. Background
Audio and other media devices often include a jack for receiving a media plug coupled to a peripheral device. For example, a mobile phone may include a jack for receiving a plug coupled to an audio headset with microphone, which allows a user to carry on a voice conversation over the mobile phone using the headset. Other example media devices include MP3 players, handheld gaming devices, tablets, personal computers, notebook computers, personal digital assistants, etc., while other peripheral devices include headphones, hearing-aid devices, personal computer speakers, home entertainment stereo speakers, etc.
Stereo headphones often have a finite resistance in their ground path that is common to both the left and right channels. This finite ground resistance may cause crosstalk between the left and right channels of a stereo headphone, i.e., the left channel signal may be present on the right channel, and vice versa. For example, assuming 16 mΩ of ground resistance in a 16-Ω stereo headphone, the right channel signal will appear in the left channel attenuated by a factor of 1000 (−60 dB), and the left channel signal will appear in the right channel attenuated by a factor of 1000 (−60 dB). Thus, there will be as much as −60 dB of crosstalk present.
It would be desirable to provide simple and effective techniques for eliminating crosstalk between the left and right channels of a stereo system.